<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>transition-delay</title>
<style type="text/css">
body { background: #abcdef; }
div { width: 800px; height: 800px; margin: auto; transform: rotate(0deg); background: url(images/imooc.png) no-repeat center center, url(images/circle_outer.png) no-repeat center center;
    -webkit-transition-property: transform;
       -moz-transition-property: transform;
        -ms-transition-property: transform;
         -o-transition-property: transform;
            transition-property: transform;
    -webkit-transition-duration: 2s;
       -moz-transition-duration: 2s;
        -ms-transition-duration: 2s;
         -o-transition-duration: 2s;
            transition-duration: 2s;
    -webkit-transition-timing-function: ease-in-out;
       -moz-transition-timing-function: ease-in-out;
        -ms-transition-timing-function: ease-in-out;
         -o-transition-timing-function: ease-in-out;
            transition-timing-function: ease-in-out;
    -webkit-transition-delay: 1s;
       -moz-transition-delay: 1s;
        -ms-transition-delay: 1s;
         -o-transition-delay: 1s;
            transition-delay: 1s;
}
div:hover { cursor: pointer; transform: rotate(180deg);
    -webkit-transition-property: transform;
       -moz-transition-property: transform;
        -ms-transition-property: transform;
         -o-transition-property: transform;
            transition-property: transform;
    -webkit-transition-duration: 2s;
       -moz-transition-duration: 2s;
        -ms-transition-duration: 2s;
         -o-transition-duration: 2s;
            transition-duration: 2s;
    -webkit-transition-timing-function: ease-in-out;
       -moz-transition-timing-function: ease-in-out;
        -ms-transition-timing-function: ease-in-out;
         -o-transition-timing-function: ease-in-out;
            transition-timing-function: ease-in-out;
    -webkit-transition-delay: 1s;
       -moz-transition-delay: 1s;
        -ms-transition-delay: 1s;
         -o-transition-delay: 1s;
            transition-delay: 1s;
}
</style>
</head>
<body>
<div></div>
</body>
</html>